Firearm.



@FFlQEg aanname. l

.To olii whom t may concern: Y Y Be it hnovvn that l, Lnnor T. Hmm/ran,a citizen ci the United States, and resident of' atertonfn, in thecounty of Middlesex and State of Massachusetts, have invented new andusefull improvements in Firearmsg of which the :following aspecification.

This invention relates to so-called automatic firearms ci" the type inwhich the reen vvard movement or elongation of the can tridge caseresulting from the explosion of the charge, automaticaliy operates asoli. loading breech mechanism.

lin lirearnis ofv this character a longitudinally movable bol-t headmade with a stein is held against the end of the cartridge at the timeof firing, and a longitudinally Inovahle breech bolt is held against thebolt head stein, la, locking sleeve surrounds the breech boit and theo1"- the bolt head. The locking; sleeve is mounted in the receiverbehind cartridge chamber in such manner yboth to rotate and to slidelengthwise and the breech holt is mounted to slide length- Wise but notto rotate. The locking sleeve has a lng' cooperating with a shoulder on.

the receiver of the firearm to lock the sleeve against longitudinalmovement When the breech is closed and the parts are in posi-- tionready for tiring, lout when the locking sleeve is given a partialrotation, the lug is disengaged from the'slioulder and the sleeve isfree to move rearwardly. rilhere is a pin and caingroove connectionbetween the breech bolt and the locking sleeve adapted to permit thebreech bolt to move rearwardly Without aiiecting the locking sleeveduriingn the irst part of its stroke. The continued rearward incrementof the breech bolt acts through the pin and cam-groove connection torotate the locking sleeve suinciently to locking sleeve lug ron'i theshoulder and, the remainder of the movement of the breech bolt carriesthe loching sleeve and the bolt head rearwardly with it; thus openingthe breech. The rearward movement of the breech bolt sets in motion atrain of mechanism which automatically ejects the spent cartridge casewhen the breech is open, inserts a new cartridge from. a suitablemagazine and restores all parts to position ready for firing. Themechanisms Vlor ejecting the case of the spent cartrit ge, forautomatically reloading9 for end firing., and sundry other associatedmechanisms form no part ot the invention Speclcation. of Letters Patent.

Patented Feb'. 11, 19ML application le September 21, 1916. Serial No.121,569.

and need not be further described nor shown in the drawings. Thisinvention has to do.

Referring to the drawings, l represents the barrel of a rifle having acartridge chainber 2, and 3 represents the receiver in which the end ofthe barrel is secured. In the receiver at the rear of the cartridgechamber, is mounted the locking sleeve 4c which has a locking lug notshown) of usual construction in breech mechanism of this characterengaging a shoulder on the receiver to lock the sleeve in the positionshown with the parts ready for iring. The locking sleeve is rotatable todisengage the locking lug from theshoulder and when so unlocked ismovable rearwardly ,to open the breech. The breech bolt 5 is mounted toslide Within the locking sleeve but not to rotate. There is the usualpin and cam-groove connection (not shown) between the breech bolt 5 andthe locking sleeve 1i by which the bolt 5 is permitted to make the firstpart of its rearward movement Without rotating the locking sleeve 4, andwhereby the continued rearward movement of the bolt 5 will im part tothe locking sleeve apartial rotation thereby unlocking the sleeve afterwhich the bolt carries the sleeve rearwardly to open l the breech. Y l

The bolt head 6 is made with a stem or neck 7 which extendsinto thelocking sleeve a and into contact with the end of the breech bolt whenthe parts are in position ready for firing. The `tace of the bolt headis formed to engage and grip the end 'of a cartridge C within thecartridge chamber, and a firing pin 8 extends through the breech boltand bolt head into contact with the end of the cartridge. to fire thelatter when driven forward by the hammer or equivro lent mechanism.

The parte thus for described may be sub- 'cause the cartridge case toelongate, and as the forward end of the cartridgecase abuts against theshoulder 9 of the cartridge chamber, suoli elongation takes placerearwardly.n

The rearward motion of the end of the car tridge case forces *he boltheadrearwardly, suhcient space being provided therefor between the bolthead 6 andthe end of the locking sleeved, whereupon the breech bolt 5 isdriven rearwardly by .the neck 7 of the bolt head. The breech bolt 5during this rearward movement partially rotates and unlocks the lockingsleeve 4 as already described, carries the locking sleeve 4 and bolthead rearwardly to yopen the breech, and operates the mechanism forejecting vthe case of the spent cartridge and for reloading the firearm.

Upon the explosion of the vcharge in the cartridge, and while the a-spressure resulting from the explosion is at 0r near the maximum, thecartridge case expands momentarilythereby bin ing the case within thewalls of the cartridge chamber at the instant of high pressure. Therearward impulse given the cartridge case at the instant of firing,resisted by this bindingy of the case in the cartridge chamber causesthe cartridge case to elongate, and it has been found in practice,particularly with service ammunition or other ammunition developing highpressure, that without some support or counter resistance for the end ofthe cartridge until the pressure of the gases of combustion is so farreduced as to relieve the` binding of the case within the cartridgechamber, the cartrid ge case Will frequently rupture leavingA the orwardend of thecase in the c amber.

The principal object of thepresent invention is to provide means for soconstraining or retarding the lrearward movement of the bolt head 6 ator about the time of maximum pressure, that the bolt head will offersufficient resistance to the resulting sudden rearward movement oftheend ofthe cartridge case to prevent the latter from rupturing.

To this end I rovide a spring, which may be of any suita le form,between the bolt head 6 and the end of the locking sleeve 4,' which willoffer suiicient resistance to the sudden rearward movement of `the bolthead 6 at or about the time of maximum pressure to allow the elon ationand rearward thrust of the cartridge case to take i place graduallywithout rupturing the case.

e5 their perpheries or their crowns in contacty In the preferred form,such spring consists of a series of sti spring disks 10 slightlyconca'vo-convex as shown and arranged with or alternately orsuccessively with their p eripheries and crowns 1n contact, as shown inF ig. 1. Three such disks are shown in thek drawings; but the number ofdisks and the extent of their' possible deflection may be variedaccording to the extent of movement of the bolt head 6 which is' desiredin the' drives the breech bolt 5 rearwardly as usual,

unlocking the locking sleeve and actuating the ejecting and reloadingmechanisms.

1. A firearm comprising, in combination, a cartridge chamber, a lockingsleeve movable longitudinally toward and away fram the cartridgechamber, a breech bolt mounted to slide longitudinally of the lockingsleeve, a bolt head, rthe forward end of which is adapted to engage theend of a cartrid e, and vthe rear end of which actuates t e breech bolt,said bolt head being mounted to move longitudinally of the lockingsleeve at the forward end thereof, and a stiff recoil spring interposedlbetween the bolt headpand 'the locking sleeve adapted yieldingly toresist the initial rearward movement of the bolt head under theinfluence of the explosion of the cartridge, whereb the said rearwardmovement of the bo t head is restrained and gradually reduced invelocity.,

. ates the breech bolt, said bolt head being mounted to movelongitudinali ,of the locking sleeve at the forward end t ereof, andaconcavo-convex spring disk interposed bei tween the bolt head and thelocking Sleeve adapted yieldingly to resist the initial rear- 'lio wardmovement of the bolt head under the influence of the explosion ofthecartridge.

' 3. AA firearm comprising, in combination, a cartridge chamber, alocking sleevemovable longitudinally toward and away from the cartridgechamber, a breech bolt mount,

ed to slide longitudinally of the locking i sleeve, a bolt head, theforward end of which is adapted to engage the end' of a cartridge, andthe rear end of which actuates the reeeh bolt, said bolt head beingmounted more longitudixially of the locking sleeve cartridge, and therear end of which actuates the breech bolt, said bolt headbeng t theforward end thereof,Y and a plurality; mounted to move longitudinally ofthe lock- -ing sleeve at the forward end thereof, and

f eoneavo-vonvex spring diskswinterposed etween the holt head and thelovking sleeve dapted yieldingly to resist the initial rear- 'ardmovement of the bolt head under thil ifluenoo of the explosion of therartridge.

4. A firearm comprising, in combination. cartridge chamber, a lockingsleeve Inovblo'longitudinally toward and away from 11e rartridgechamber, a breech bolt mount* il to slideflongitudinall)Y of the lockingIeove, a` bolt head, the forward end of hich is adapted lo engage theend of a three or more concave-convex spring disks arranged successivelyperiphery to periphery and crown to crown, interposed between the bolthead and the locking sleeve adapted yieldingly to resist the initialrearward movement of the bolt headJ'nder the influence of the explosionof the'cartridge.

y Signed hy me at New York, N. Y., this 15th day of September, 1916.

LEROY T. HILLMAN.

